134 PROCEEDINGS OF THE ACADEMY OP 



^\ Critical Eeview of the Family PROCELLARIID^ :— Part IV ; Embracing the 

 ^STKELATE^ and the PRIONEiE. 



BY DR. ELLIOTT COUES, U. S. A. 



In the present paper, the fourth of the series, are together considered the 

 u^strelatete and the Prionece, mainly for the purpose of showing liow closely 

 related these sections are through certain of their genera. 



For the first of these sections three names are at our disposal ; sc. JEsfrela- 

 tece, Daptionefe and Rhantistece. Of these I prefer to accept the first, both as 

 having priority, and being taken from the name of the typical and largest 

 genus of the group ; the second being based upon a subtypical genus with but 

 a single species, and the third being derived from Bonaparte's erroneous 

 identification of Kaup's Fulmarine genus RhaiUistes. 



The section yJ-^strelatece, as here restricted, corresponds very nearly with 1 he 

 group defined under this name in Bonaparte's Conspectus. There is here, 

 however, included in it the genus Daption*, by Bonaparte placed among the 

 Fulmarea ; and it is considered as probably connecting the u-EstrelatecK with 

 the Prions. The genus Thalassoica is excluded as being essentially Fulma- 

 rine. In generic arrangement I am compelled to difl'er widely from the dis- 

 tinguished author just named. After attentive and critical examination of his 

 genera Cuol-ilaria, Pterodroma and Bidweria, I must confess my inability to 

 distinguish either of them from yEstrelata by a degree of morphological dif- 

 ference which, by any sublimation of characterization, can be considered of 

 generic import. " Bulweria " has a rather more elongated and deci'ledly 

 cuneiform tail than have the majority of the ^strelatas ; but difi'eri from 

 some of them in this respect, no more than they do among themselves. 

 " Pterodroma" comprises some fuliginous species morphologically identical 

 with ^Estrcluta. "Cookilaria " has no characters whatever assigned to it by 

 its author ; possibly because none are to be found in the species included 

 under it. 



I do not hesitate to follow natural data afforded by specimens, even should 

 they conflict with the opinions of so justly distinguished an author as that of 

 the " Conspectus ; " especially since the more closely I scrutinize his work 

 upon the Petrels, the more irresistibly the conviction is forced upon me, that 

 it is, to speak in the mildest terms, unreliable. It cannot be denied by the 

 most strenuous of his advocates, that there are to be fo.und in this work in- 

 stances of unnecesssary if not unwarrantable pseudo-generic subdivisions ; of 

 some pure figments in the way of species ; of rash collocation of synonymy ; 

 and of weak and intangible diagnoses. These are to the last degree discoura- 

 ging, because perplexing, to the student, — crecle mlhi e.rperto. They would, 

 liowever, be less repellant, and bear much more weight, could we feel satisfied 

 that they represented the matured opinions of the author, based upon well- 

 digested facts. Such unhappily is not the case ; for the views expressed on 

 different occasions are found to fluctuate according to the particular theory 

 which may have been in posse sion of his mind at the time of writing; and 

 are often diametrically epposed to each other. That I may not seem to wan- 

 tonly criticise one of the most brilliant lights that lias ever shed its radiance 

 upon Ornithology, to whom alas ! it was not permitted to finish his last great 

 work, I may be allowed to sustain myself by a simple comparison of the 

 " Conspectus" with the Table of the Longipennines published in the Comp- 

 les Rend us. The fasciculi of the former which treat of the Petrels bear date 

 of Dec, 18.55, and Jan., 1856 ; the latter is of the seance of April 2S, 1856. I 

 only cite some of the more glaring discrepancies of generic arrangement and 

 distribution of species ; for concerning synonyma it maybe stated that as a 

 general rule conflicting views are entertained on all debatable points. 



* The true rclatioubhip of this genus is still with me a matter of some uncertainty. 



[May, 



